The turf war continues, but supporters of replacing the run-down Beach Chalet grass soccer fields at Golden Gate Park with a synthetic surface scored a major victory before the Board of Supervisors Tuesday.

After hearing nearly seven hours of arguments for and against the proposed turf fields on the western edge of the park, the board voted 10-1 just after 11 p.m. to reject an appeal of the project’s environmental impact report.

Should the real thing the stay or be replaced with synthetic turf? (Michael Macor/The Chronicle)

Attorney Richard Drury, representing S.F. Ocean Edge and several other opposition groups, claimed that the report certified by the Planning Commission in May failed to consider a “hybrid alternative” that would have kept the natural grass at Beach Chalet while installing turf and lights at fields in West Sunset.

He wasn’t able to convince Supervisor Carmen Chu.

“I simply don’t think that holds weight,” said Chu, who represents the Sunset/Parkside District adjacent to the park. “We had a number of altneratives that were provided within the environmental document. It doesn’t have to be exhaustive; it just has to have a reasonable range.”

Only Supervisor Christina Olague voted to uphold the appeal, agreeing with opponents that not enough was done to consider health risks, light pollution and a better spot for the turf fields.

“I think it goes against the character of Golden Gate Park to introduce something life AstroTurf,” Olague said. “I just don’t believe the environmental impact report was an adequate analysis.”

A long line of opponents to the synthetic fields were the first to give public testimony. Soccer moms said they worried about their kids getting exposed to chemicals associated with artificial turf and environmentalists objected to bringing an unnatural substance into a treasured green space.

Richmond resident Gabriel Lampert, who lives on 48th Avenue about two blocks from Golden Gate Park, focused his remarks on lighting concerns.

“I have to say it’s B.S. that the stadium lights would not be throwing off extra light,” said Lampert, who used to live near a bright stadium at New Mexico State University. “I know that any chance I’d have at seeing any stars at night would be gone.”

But an equally vocal and numerous contingent showed up to defend the project, filling the chambers with their soccer uniform-clad children who were all up way past their bedtimes.

Kim Freudenberg testified in support of the project alongside her son Kurt, 9. The Outer Sunset resident said Kurt tripped and fell in a gopher hole the first time he played on Beach Chalet’s grass fields.

“If Beach Chalet was a beautiful meadow, I wouldn’t be here in support of a soccer field,” she said. “But we’re not taking away anyone’s natural experience by letting kids play on a better surface that is safer.”

Turf opponents aren’t finished yet. A hearing with the Board of Appeals has been scheduled for Aug. 1, Drury said. He plans to argue that the project, specifically the 10, 60-foot stadium-style lights, violates the California Coastal Act of 1976.

“You’re not supposed to do things that interfere with the coastal zone,” Drury said. “It’s a long way before this thing gets approved.”